If I Use
My EAD While Employed on an H-1B, Does My H-1B Become Invalid?

Dr. William:

If I use my EAD while employed on an H-1B, does my H-1B become invalid? Also,
I worked on a business visa prior to H-1B status, will the business visa duration be counted towards the 6-years of H-1 duration?

Answer:

If you use your EAD while employed on an H-1B, your
H-1B will not be become invalid. You are allowed to maintain both the H-1B
status and the EAD concurrently, since there is dual intent for H-1B and your dependents on
H-4. Also, your 6-years on H-1B continues even though you have an EAD and are working based on that EAD.

The business visa duration will not be counted towards the 6- years of H-1B
duration. Your status on B-1 is not counted towards the 6-years on H-1B. However,
you are not legally allowed to work in US on B-1 visa, since B-1 is primarily meant to attend
conferences or for business trips in US.